The invention pertains to semiconductive material stencil masks, and to methods of forming semiconductive material stencil masks.
Ion and electron beam lithographic systems utilize a stencil mask to pattern a resist-coated target. These stencil masks typically comprise a substrate having a pattern of openings formed therethrough. Commonly, the substrate will be formed of silicon. However, other deposited or grown materials, such as SiC, SiN and BN can also be used to form at least a portion of the substrate.
The formation of a pattern of openings extending through substrates comprising silicon, SiC, SiN and/or BN can be quite challenging as said substrates are frequently thin and brittle. Accordingly, it would be desirable to develop alternative methods of forming a pattern of openings within such substrates.
Additionally, it can be challenging to maintain the dimension of an opening formed in a thin substrate comprising silicon, SiC, SiN and/or BN, as the material around such openings tends to easily deform (i.e., warp, bow or otherwise alter its shape after formation of the openings). Such deformations can undesirably change the dimensions of the openings and thus alter a pattern of openings formed in a stencil mask substrate. Accordingly, it is desirable to develop methods of maintaining a pattern of openings within a stencil mask substrate.
In one aspect, the invention encompasses a method of maintaining dimensions of an opening in a semiconductive material stencil mask. Two different dopants are provided within a periphery of the opening, with the dopants each being provided to a concentration of at least about 1017 atoms/cm3.
In another aspect, the invention encompasses a method of manufacturing a stencil mask from a semiconductive material. A semiconductive material stencil mask substrate is provided. The substrate has openings formed through it and has a background dopant concentration. A first dopant is provided within the substrate. The first dopant is provided to a concentration which exceeds the background dopant concentration. A second dopant is provided within the substrate. The second dopant is provided to a concentration which exceeds the background dopant concentration.
In another aspect, the invention encompasses a semiconductive material stencil mask. The stencil mask includes a semiconductive material substrate having an opening therethrough. The opening is defined by a periphery comprising the semiconductive material. The stencil mask further includes two different dopants within the semiconductive material at the periphery. The two different dopants are of a same conductivity type as one another.